• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.22 no.1
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• pp.97-108
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• 1992

The author obtained 120 oblique-lateral transcranial radiograms by two projection methods from 30 subjects with clinically normal TMJ. The relative position of the condyle within the articular fossa and the quality of the radiographic images were compared in the standardized and individualized radiographic groups. The results were as follows: 1. The condylar position in the individualized radiographic group was more posterior than that in the standardized radiographic group (P<0.001). 2. The horizontal angle between the long axis of condyle and intermeatal line in the individualized group ranged from 0° to 31° (14.38°±7.55°), and the highest prevalence was found between 15 and 19° 3. The individualized group showed prominent radiopaque shadow of the anterior condylar border; the image detail was superior in the standardized group to that of the individualized group (P<0.05).

• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.1
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• pp.63-71
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• 2014

This study presents an experimental study of the structural behavior for steel plate-concrete column-to-steel girder connections. Experiments were carried out to investigate the moment-rotation characteristics, failure behavior and ultimate moment capacity of these connections. The results of this experimental study involving three welded moment-resisting connections subjected to cyclic loading are presented. The specimens were fabricated at full scale to evaluate their hysteretic behavior. A description of the test specimens, the details of the joint, the test system and the testing methods are described. The test results showed that the structural behavior of these composite connections was influenced by the connection details.

• Coupled systems mechanics
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• v.7 no.5
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• pp.627-634
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• 2018

Laser beam welding is more advantageous compared to conventional methods. Titanium/Aluminium dissimilar alloy thin sheet metals are difficult to weld due to large difference in melting point. The performance of the weldment depends upon interlayer formation and distribution of intermetallics. During welding, aluminium gets lost at the temperature below the melting point of titanium. Therefore, it is needed to improve a new metal joining techniques between these two alloys. The present work is carried for welding TI6AL4V and AA2024 alloy by using Nd:YAG Pulsed laser welding unit. The performance of the butt welded interlayer structures are discussed in detail using hardness test and SEM. Test results reveal that interlayer fracture is caused near aluminium side due to low strength at the weld joint.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.1-6
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• 2002

The study offer a suggestion that from result in being a case to efflorescence for decrease a plan: $\circled1$ A efflorescence of concreat a structure will be the prograss plan; In the materials, depress use to the water-sand in the construction, admonish unification of front and rear in the environment, consideration requisite concreat don't the occurrence efflorescence. $\circled2$ Ma sonry building efflorescence establish a ventilation opening and a waterway to ma sonry the times avoid the winter or the rainy season. Ma sonry building efflorescence will be make good among a brick to a brick interval closely mortar. $\circled3$ Tile building, tile of plasticity temperature is appropriate, reduce the deviation, parapet part of efflorescence will be make good closely mortar. A construction material part a meterial developing need Perfection of construction a efflorescence occurrence is the minimum, a plan Part developed so on, composition of a ommection field systematic effort need a efflorescence Prevention a kind of detail.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.135-142
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• 2007

MADYMO human model with the detail neck was used to investigate the reaction force of neck and neck injury from rear impact directions. In the validation simulation, head acceleration, thorax acceleration and the global kinematics of the head and neck were correlated well with experimental data. Acceleration data from three 15 km/h low speed car rear impact pendulum tests(rear-end, offset, oblique) were used to simulate the model. In the simulation results, the reaction force on the facet joint and discs in the oblique rear impact were higher than rear-end, offset rear impacts. Further research is still needed in order to neck injury analysis about different crash parameters.

• Journal of the Korean Society of Combustion
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• v.4 no.2
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• pp.51-62
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• 1999

NOx formation in turbulent flames is strongly coupled with temperature, superequilibrium concentration of O radical, and residence time. This implies that in order to accurately predict NO level, it is necessary to develop sophisticated models able to account for the complex turbulent combustion processes including turbulence/chemistry interaction and radiative heat transfer. The present study numerically investigates the turbulent nonpremixed hydrogen jet flames using the laminar flamelet model. Flamelet library is constructed by solving the modified Peters equations and the turbulent combustion model is extended to nonadiabatic flame by introducing the enthalpy defect. The effects of turbulent fluctuation are taken into account by the presumed joint PDFs for mixture fraction, scalar dissipation rate, and enthalpy defect. The predictive capability of the present model has been validated against the detailed experimental data. Effects of nonequilibrium chemistry and radiative heat loss on the thermal NO formation are discussed in detail.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.93-104
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• 1999

NOx formation in turbulent flames is strongly coupled with temperature, superequilibrium concentration of O radical, and residence time. This implies that in order to accurately predict NO level, it is necessary to develop sophisticated models able to account for the complex turbulent combustion processes including turbulence/chemistry interaction and radiative heat transfer. The present study numerically investigates the turbulent nonpremixed hydrogen jet flames using the laminar flamelet model. Flamelet library is constructed by solving the modified Peters equations and the turbulent combustion model is extended to nonadiabatic flame by introducing the enthalpy defect. The effects of turbulent fluctuation are taken into account by the presumed joint PDFs for mixture fraction, scalar dissipation rate, and enthalpy defect. The predictive capability of the present model has been validated against the detailed experimental data. Effects of nonequilibrium chemistry and radiative heat loss on the thermal NO formation are discussed in detail.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.10a
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• pp.230-238
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• 1996

Recently, square hollow section (S.H.S) is frequently used for column and H-section for beam of steel building structures. The connection between S.H.S column and H-beam is found to weaken the rotational restraint of the joint. Several types of detail to overcome the problem have been suggested for the connection between concrete filled S.H.S column and concrete composited H-bean In this paper, modelling technique to monitor the behavior of the connections is proposed. Then, Drucker-Prager yield criteria is introduced to simulate yield behavior of in-fill concrete while Von-Mises was used in earlier works. Gap-elements are also introduced to simulate the interaction between S.H.S columns and the in-fill concrete as in privious papers. axial forces are applied to S.H.S columns and made to vary in intensity and eccentricity.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.29-30
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• 2009

In this study, analyzing loads transferred to the piles, both easily constructed and mechanically improved pile head design method for the PHC pile is presented. To compare with mechanical capacity of the existing and proposed method, tensile, compression, moment, and shear tests are performed with 11 pieces of full-scaled blocks. As a result, mechanical capacities of the proposed method is superior to those of existing one in all aspects and work efficiency as well.

• Journal of Korean Association for Spatial Structures
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• v.6 no.2 s.20
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• pp.85-92
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• 2006

Precast large panel structures have various connection system such as the horizontal slab-to-wall connection, the vertical wall to wall connection, horizontal slab-to-slab connection, etc. Horizontal connection is connected by vertical tie bars, and vertical joint is connected loop bars and shear keys. The basic function is equalized deformations on later forces and the entire wall panel assembly acts as monolithic actions. Under lateral load some slip occurs in almost vertical connections. The shape and detail of precast connections are very important to the monolithic behavior of overall structures. The paper is a study on the design method and new elasto-plastic analysis of the connections by rigid-bodies spring model.